The present disclosure relates generally to vehicle structures, and more particularly to a reinforcement for a vehicle structure.
In current vehicle structures, it has become challenging to obtain space within the vehicle to implement components that absorb impact energy created during a vehicle crash. Conventional designs for absorbing high-energy impacts, such as that described in U.S. Pat. No. 3,931,997 to Myers, typically include structures that are made from high strength materials like various high strength steels. These tubular structures may be designed as vehicle rails, or may be separately positioned in fore/aft direction of the vehicle to absorb the energy of a fore/aft collision. However, such designs have a tendency to buckle laterally if the load is offset, that is, if the load is not concentric with the tube. Moreover, because of the limited space available in the vehicle and because of the limited frame selection allowed, improving the axial strength of such structures tends to increase the degree of lateral instability of the tubes.
Other conventional designs include crush cans or crush tubes that are welded or mechanically fastened to one end of a rail and a vehicle bumper such as that shown in U.S. Pat. No. 5,876,078 issued to Miskech. The crush cans or crush tubes that are implemented in Miskech, as indicated above, has a tendency to buckle laterally if the load is not concentric with the tube.
As shown in FIGS. 1 and 2 together, a prior art crush tube assembly 110 of the '593 patent is illustrated. The crush tube assembly 110 includes a tube 118 which is disposed within a two piece stamped body structure 116 but does not additional length to the underlying structure. The tube 118 is welded into one of stamped members and then the mating stamped member is subsequently installed to create a closed section. The crush tube assembly 110 of the prior art design requires a two-pieced stamped body structure 116 which is generally greater in weight and cost. Furthermore, such a design results in increased assembly or manufacturing time.
As indicated, other systems may be used to absorb impact energy by including an entire redesign of an automotive vehicle body structure, such as for example the vehicle body structure described in U.S. Pat. No. 6,312,038 to Kawamura, et. al. Such designs may include extensions of the vehicle body frame in the fore/aft direction in order to accommodate one or more energy absorbing members.
Such redesigns, however, are more expensive to develop and are not compatible with automobiles in present production regardless of the area of the vehicle where increased energy absorption is desired. In particular, presently produced automobiles may not have the necessary packaging space available for housing an increased number of absorbing members, or tubes.